The present invention relates to a small size multi-way water proof connector with an improved water proof property between a connector housing and a plurality of electric wires connected with terminals, and a method of assembling the same.
A related waterproof connector, which is disclosed in Japanese Patent Publication No. 11-329571A, will be explained specifically with reference to FIGS. 2 to 4E. A connector housing 11 of a water proof connector 10' comprises a synthetic resin inner housing 12 having a plurality of terminal chambers 13 formed integrally therewith, a synthetic resin outer housing 17 for fitting the inner housing 12 to the inside thereof, and a synthetic resin spacer 28 disposed between the inner housing 12 and the outer housing 17 for holding female terminals 14 accommodated in each terminal chamber 13 of the inner housing 12. p As shown in FIGS. 2 and 3, the inner housing 12 has a box part 12a with the rear side of the upper and lower faces opened, for forming the terminal chambers 13 in a space formed with the center horizontal wall 12b and vertical side walls 12c, serving also as partition walls in the vertical direction. The female terminals 14 can be accommodated in each terminal chamber 13. Moreover, engagement claws 15 are formed integrally, projecting from both sides and the center of the upper and lower faces of the box part 12a as well as flange parts 16 are formed integrally projecting from the front end of the both side center parts. Rectangular insertion holes 12d through which female terminals of a mating connector (not illustrated) are inserted are formed in the front wall of the box part 12a at a position corresponding to each terminal chamber 13. Furthermore, a pair of press-connecting blades 14b, 14b are formed by bending each in both side plate parts in the rear part of a box part 14a of the female terminals.
As shown in FIGS. 2 and 3, the outer housing 17 has a double box-like shape with the front side opened, with a substantially quadrilateral pipe-like inner wall part 17a, a substantially quadrilateral pipe-like outer wall part 17b for containing the inner wall part 17a, and a bottom wall part 17c, connecting the rear parts of the inner and outer wall parts 17a, 17b. A thick portion is provided in the center of the bottom wall part 17c. Rubber plug chambers 19 having a large diameter round cross-section for storing the water proof rubber plugs 18 by press-in are formed at a position corresponding to each terminal chamber 13 at the front side with respect to the thick portion as well as insertion holes 21 having a small diameter round cross-section for inserting electric wires 20 therethrough are formed, communicating with each corresponding rubber plug chamber 19 at the rear side with respect to the thick portion. The water proof rubber plugs 18 have a substantially cylindrical shape with the rugged inner and outer circumferential faces so that the electric wires 20 can be inserted through the inside thereof without having a gap.
Moreover, rectangular engagement holes 22 to be engaged with each engagement claw 15 at both sides of the upper and lower faces of the box part 12a of the inner housing 12 are formed at both front sides of the upper and lower walls of the inner wall part 17a of the outer housing 17 as well as rectangular longitudinal engagement holes 23 to be engaged with each engagement claw 15 at the center of the upper and lower faces of the box part 12a of the inner housing 12 are formed at the front center portion of the upper and lower walls of the inner wall part 17a. Furthermore, a V-shaped packing receiving part 25 for receiving an annular rubber water proof packing 24 is formed integrally, projecting from the deep part of the outer face side of the inner wall part 17a of the outer housing 17. Tapered faces 26 are formed in the front rim of the inner face side of the inner wall part 17a of the outer housing at a position corresponding to each engagement hole 22, 23. Moreover, engagement holes 27 to be engaged with flexible engagement arms of a mating connector (not illustrated) are formed at the front side of the upper and lower walls of the outer wall part 17b of the outer housing 17.
As shown in FIGS. 2 and 3, the spacer 28 forms a box-like shape with the front side opened, with a substantially quadrilateral pipe-like body 28 to be fitted with the inner face side of the inner wall part 17a of the outer housing 17, a substantially quadrilateral pipe-like brim part 28b formed integrally with the front end of the body 28a, bent rearward therefrom, to be fitted with the outer face side of the inner wall part 17a of the outer housing, and a bottom wall part 28c of the body 28a.
Accordingly, the box part 12a of the inner housing 12 can be fitted into the body 28a of the spacer 28. Rib-like projections 29 for preventing fall-off of the terminals are formed integrally, projecting from the inner face of the upper and lower walls of the body 28a of the spacer 28, to be engaged with the rear end rim of the box part 14a of the female terminals 14 accommodated in each terminal chamber 13.
Moreover, notch portions 30, 31 are formed in the front side of the portion connecting the body 28a and the brim part 28b of the spacer 28 at a position corresponding to each of the engagement claw 15 and the flange part 16 of the inner housing 12. Engagement claws 32 to be engaged with each engagement hole 23 of the outer housing 17 are formed integrally, projecting form the outer face side of the upper and lower walls of the body 28a of the spacer 28 between the upper and lower side notch portions 30. Furthermore, the tip portion of the brim part 28b can hold the packing 24 engaged with the packing receiving part 25 of the inner wall part 17a of the outer housing 17 when the fitting operation with respect to the outer housing 17 is completed.
Moreover, insertion holes 33 are formed in the bottom wall part 28c of the spacer 28 at a position corresponding to each insertion hole 21 of the outer housing 17. Furthermore, the bottom wall part 28c of the spacer 28 can hold the rubber plugs 18 inserted in each rubber plug chamber 19 of the bottom wall part 17c of the outer housing when the fitting operation with respect to the outer housing 17 is completed. As shown in FIG. 2, each electric wire 20 inserted through each insertion hole 21 of the outer housing 17, each rubber plug 18 and each insertion hole 33 of the spacer 28 is press-connected between the pair of the press-connecting blades 14b, 14b of each female terminal accommodated in each terminal chamber 13 of the inner housing 12 so that each terminal chamber 13 and each electric wire 20 are sealed with the rubber plug 18 and the packing 24, respectively.
In assembling the water proof connector 10' with the above-mentioned configuration, as shown in FIG. 4A, the rubber plugs 18 are inserted and set in each rubber plug chamber 19 inside the bottom wall part 17c of the outer housing 17 comprising the outside of the connector housing 11 from the connector housing fitting direction as well as the packing 24 is inserted and set in the packing receiving part 25 of the inner wall part 17a of the outer housing 17.
Then, as shown in FIG. 4B, the body 28a of the spacer 28 is fitted into the inner wall part 17a of the outer housing 17 so that each engagement claw 32 of the body 28a of the spacer 28 is engaged with each engagement hole 23 of the inner wall part 17a of the outer housing 17. According to the engagement of each engagement hole 23 of the inner wall part 17a of the outer housing 17 and each engagement claw 32 of the body 28a of the spacer 28, fall-off of each rubber plug 18 is prevented by the bottom wall part 17c of the outer housing 17 as well as fall-off of the packing 24 is prevented by the oblique tip end of the brim part 28b of the spacer 28 so that the water proof property of the connector housing as a whole can further be improved.
As shown in FIG. 4C, the electric wires 20 are inserted through each insertion hole 21 of the bottom wall part 17c of the outer housing 17, each rubber plug 18, and each insertion hole 33 of the bottom wall part 28c of the spacer 28 from the outside. Then, as shown in FIG. 4D, each electric wire 20 is press-connected with the pair of the press-connecting blades 14b, 14b of the female terminals 14 accommodated in each terminal chamber 13 of the inner housing 12 comprising the inner side of the connector housing 11.
As shown in FIG. 4E, the inner housing 12 is fitted into the body 28a of the spacer 28 so that each engagement claw 15 of the box part 12a of the inner housing 12 is engaged with each engagement hole 23 of the inner wall part 17a of the outer housing 17 so as to complete the assembly of the water proof connector 10'. At the time, since the rear end rim of the box part 12a of the inner housing 12 and the rear end rim of the box part 14a of the female terminals 14 accommodated in each terminal chamber 13 are locked according to each projection 29 projecting to the inner face of the upper and lower walls of the body 28a of the spacer 28 as well as each projection 29 cannot deform outward, fall-off of the female terminals 14 from each terminal chamber can be prevented certainly. Besides, since the spacer 28 can hold each female terminal 14 and each rubber plug 18 at the same time, a component dedicated to prevention of fall-off of the rubber plug can be eliminated, and thus a low cost can be achieved by cutback of the number of the components. Furthermore, since the spacer 28 can be locked doubly according to the engagement of each engagement claw 32 of the spacer 28 itself with each engagement hole 23 of the outer housing 17 and the engagement of each engagement claw 15 o the inner housing 12 with each engagement hole 23 of the outer housing 17, fall-off of each rubber plug 18 and the packing 24 can be prevented certainly so that the water proof reliability can further be improved.
However, according to the related water proof connector 10', since the rubber plugs 18 are accommodated preliminarily in the rubber plug chambers 19 of the outer housing 17 as shown in FIG. 4B, the electric wires 20 can easily be bent due to the sliding friction between the rubber plugs 18 and the electric wires as shown in FIG. 5 at the time of the electric wire insertion by inserting the electric wires 20 through the insertion holes 21 of the outer housing 17 and the insertion holes 33 of the spacer 28 shown in FIGS. 4B to 4C, and at the time of fitting the housing by sliding the electric wires 20 with respect to the insertion holes 33 of the spacer 28 and the insertion holes 21 of the outer housing 17 so as to fit the inner housing 12 into the spacer 28 fitted inside the outer housing 17 shown in FIGS. 4D to 4E so that there is a risk of causing a trouble in the wire harness production. That is, there is a risk of deteriorating the assembly operativity of the water proof connector 10' due to the increased operation load by the sliding friction between the rubber plugs 18 and the electric wires 20 at the time of the electric wire inserting operation of the electric wires 20 and the housing fitting operation of fitting the inner housing 12 into the outer housing 17 side.
Moreover, since the function of preventing the fall-off of the rubber plugs 18 is provided to the spacer 28, the longitudinal body 28a for integrally forming the bottom wall part 28c for holding the rubber plugs 18 is indispensable in the spacer 28, resulting in bulkiness of the water proof connector 10'.